https://leetcode.cn/problems/aMhZSa/
思想：将链表遍历一遍，将遍历到的数字存放到数组中进行判断

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode() : val(0), next(nullptr) {}
 *     ListNode(int x) : val(x), next(nullptr) {}
 *     ListNode(int x, ListNode *next) : val(x), next(next) {}
 * };
 */
class Solution {
public:
    bool isPalindrome(ListNode* head) 
    {
        vector<int> a,b;
        stack<int> c;

        ListNode *p = head;
        while(p != nullptr)
        {
            a.push_back(p->val);
            c.push(p->val);
            p = p->next;
        }

        while(!c.empty())
        {
            b.push_back(c.top());
            c.pop();
        }

        for(int i = 0; i < a.size(); i++)
        {
            if(a[i] != b[i])
            {
                return false;
            }
        }

        return true;
    }
};